Обсуждение: Bad error message

From -HEAD:

ERROR:  aggregates not allowed in WHERE clause
STATEMENT:  SELECT *                FROM loans l                WHERE id IN (   SELECT max(l.id)
           FROM loans                                        JOIN customers c ON c.id =  
 
l.customer_id                                        JOIN people p ON p.id =  
c.person_id                                    WHERE p.first_name = 'Test person'
GROUPBY l.loan_type_cd                            )        ;
 

The real issue is this:

ERROR:  missing FROM-clause entry for table "l" at character 132
STATEMENT:  SELECT max(l.id)                                            FROM loans
         JOIN customers c ON  
 
c.id = l.customer_id                                                JOIN people p ON  
p.id = c.person_id                                            WHERE p.first_name =  
'Test person'                                            GROUP BY l.loan_type_cd;

And if I change the FROM loans to be FROM loans l, the original  
select does work fine.

Let me know if I need to create a full test case for this...
-- 
Decibel!, aka Jim C. Nasby, Database Architect  decibel@decibel.org
Give your computer some brain candy! www.distributed.net Team #1828

"Gurjeet Singh" <singh.gurjeet@gmail.com> writes:
> On Wed, Oct 1, 2008 at 3:07 AM, Decibel! <decibel@decibel.org> wrote:
>> ERROR:  aggregates not allowed in WHERE clause

> No, the real issue is that you are referencing the outer table's column's
> max() in the inner query (correlated sub-query).

Yeah.  It's not easy to see how the software could guess your real
intentions here.  We could maybe offer a vaguely-worded HINT but I'm
not able to think of wording that would be very helpful.
        regards, tom lane

On Oct 1, 2008, at 12:12 AM, Gurjeet Singh wrote:
> On Wed, Oct 1, 2008 at 9:39 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> "Gurjeet Singh" <singh.gurjeet@gmail.com> writes:
> > On Wed, Oct 1, 2008 at 3:07 AM, Decibel! <decibel@decibel.org>  
> wrote:
> >> ERROR:  aggregates not allowed in WHERE clause
>
> > No, the real issue is that you are referencing the outer table's  
> column's
> > max() in the inner query (correlated sub-query).
>
> Yeah.  It's not easy to see how the software could guess your real
> intentions here.  We could maybe offer a vaguely-worded HINT but I'm
> not able to think of wording that would be very helpful.
>
> Can we do something like this in the code:
>
>     if( "level of the referenced column's  relation" != "level of  
> the (sub)query being processed" )
>         errhint( "The subquery may be unintentionally referencing  
> an outer query's column!" );

Yeah, something like that would be very helpful.

> Mail sent from my BlackLaptop device


Haha. +1
-- 
Decibel!, aka Jim C. Nasby, Database Architect  decibel@decibel.org
Give your computer some brain candy! www.distributed.net Team #1828